@btnH: 80px;
@btnColor: orange;
@borderColor: #e1e1e1;
@navH: 90px;

.btn() {
    background: @btnColor;
    padding: 0 30px;
    height: @btnH;
    line-height: @btnH;
    font-size: 28px;
    color: #fff;
    border: none;
    border-radius: 5px;
}